Purgatory is a tower that offers a group of convicts a second chance at life, if they can survive the climb. But who built the tower, and for what purpose are they holding this "contest"? The answer lies at the top, if they can manage to reach it.

Karmal, Nastasia and Scare live in a huge ancient building they call 'the black cathedral'. As they find out more about each other and the strange place they call 'home', they find that everything and everyone has secrets. complicated ones.